Field of the Invention
The present invention relates to a cleaning apparatus which removes a residue such as toner at a surface of an image carrying member from the surface of the image carrying member with the use of a cleaning member and an image formation apparatus including such a cleaning apparatus.
Description of the Related Art
In an image formation apparatus such as a copying machine, a printer, a facsimile machine, and a multi-functional peripheral, after a toner image is transferred from an image carrying member which moves as carrying the toner image on a surface thereof, a residue such as toner which remains at the surface of the image carrying member has conventionally been removed from the surface of the image carrying member with a cleaning apparatus. For example, after a toner image formed on a photoconductor is transferred to an intermediate transfer element such as an intermediate transfer belt or a recording sheet, a residue such as toner which remains at the surface of the photoconductor is removed with a cleaning apparatus, or after the toner image transferred to the intermediate transfer element is transferred to a recording sheet, a residue such as toner which remains at the surface of the intermediate transfer element is removed with the cleaning apparatus.
An apparatus which removes a residue such as toner which remains at a surface of an image carrying member from the surface of the image carrying member by directing a tip end portion of a cleaning member formed from a plate-shaped cleaning blade generally composed of an elastic material such as urethane in a direction opposite to a direction of movement of the surface of the image carrying member so as to have the tip end portion of the cleaning blade abut on the surface of the image carrying member has conventionally been known as such a cleaning apparatus.
When the tip end portion of the cleaning blade abuts on the surface of the image carrying member so as to face the direction opposite to the direction of movement of the surface of the image carrying member, friction resistance between the surface of the image carrying member and the tip end portion of the cleaning blade may become great due to adhesion of a product resulting from discharging during printing or fluctuation in environment. In such a case, the tip end portion of the cleaning blade which abuts on the surface of the image carrying member is pulled toward downstream in the direction of movement due to friction with the surface of the moving image carrying member, and the tip end portion of the cleaning blade gradually deforms. Therefore, the tip end portion of the cleaning blade is flipped over toward downstream in the direction of movement of the surface of the image carrying member and a residue cannot appropriately be removed from the surface of the image carrying member.
In Japanese Laid-Open Patent Publications Nos. 4-172486 and 2008-102322, as shown in FIG. 1, a cleaning member in which one side of a support member 2b formed from a leaf spring is fixed to a fixing member 2a and an abutment member 2c formed from an elastic body is attached to a tip end portion of support member 2b is employed as a cleaning member 2 which removes a residue t such as toner which remains at a surface of an image carrying member 1. The tip end portion of abutment member 2c attached to the tip end portion of support member 2b abuts on the surface of image carrying member 1 at a prescribed abutment pressure with a tip end side of support member 2b in cleaning member 2 facing a direction opposite to a direction of movement of the surface of image carrying member 1, so that residue t such as toner which remains at the surface of image carrying member 1 is removed from the surface of image carrying member 1.
When the tip end portion of abutment member 2c attached to the tip end portion of support member 2b abuts on the surface of image carrying member 1 at a prescribed abutment pressure so as to face the direction opposite to the direction of movement of the surface of image carrying member 1, however, with increase in friction resistance between the surface of image carrying member 1 and the tip end portion of abutment member 2c attached to the tip end portion of support member 2b due to adhesion of a product resulting from discharging during printing or fluctuation in environment, torque necessary for moving the surface of image carrying member 1 increases. With increase in friction resistance, as in the case of the cleaning blade, the tip end portion of abutment member 2c is pulled toward downstream in the direction of movement due to friction with the surface of moving image carrying member 1 and gradually deforms. Then, the tip end portion of abutment member 2c is flipped over toward downstream in the direction of movement of the surface of image carrying member 1 and a residue cannot appropriately be removed from the surface of image carrying member 1, or the tip end portion of support member 2b to which abutment member 2c is attached abuts on the surface of image carrying member 1 and damages the surface of image carrying member 1.
In Japanese Laid-Open Patent Publications Nos. 2013-50527 and 2013-238892, as shown in FIG. 2, cleaning member 2 in which one side of support member 2b formed from a leaf spring is fixed to fixing member 2a and abutment member 2c formed from an elastic body is attached to the tip end portion of support member 2b is employed. The tip end portion of abutment member 2c attached to the tip end portion of support member 2b abuts on the surface of image carrying member 1 at a prescribed abutment pressure so as to face the direction opposite to the direction of movement of the surface of image carrying member 1, to thereby remove residue t such as toner which remains at the surface of image carrying member 1 from the surface of image carrying member 1. Here, a bent portion 2b1 obtained by bending support member 2b toward upstream in the direction of movement of the surface of image carrying member 1 is provided between one end portion of support member 2b fixed to fixing member 2a and the tip end portion of support member 2b to which abutment member 2c is attached, to thereby reduce torque in movement of image carrying member 1 and to prevent the tip end portion of abutment member 2c from being flipped over as being pulled toward downstream in the direction of movement due to friction with the surface of moving image carrying member 1.
When bent portion 2b1 obtained by bending support member 2b toward upstream in the direction of movement of the surface of image carrying member 1 is provided between one end portion of support member 2b fixed to fixing member 2a and the tip end portion of support member 2b to which abutment member 2c is attached, with wear of the tip end portion of abutment member 2c due to long-term use, it becomes difficult to have the tip end portion of abutment member 2c abut on the surface of image carrying member 1 at a sufficient abutment pressure. Thus, residue t cannot sufficiently be removed from the surface of image carrying member 1 and cleaning becomes poor.